Matter and Radiation

Question 1

What is the charge of a proton?

Answer 1

+1.6x10⁻¹⁹

Question 2

What is the charge of an electron?

Answer 2

-1.6x10⁻¹⁹

Question 3

What is the mass of a proton/neutron?

Answer 3

1.67x10⁻²⁷

Question 4

What is the mass of an electron?

Answer 4

9.11x10⁻³¹

Question 5

What is specific charge?

Answer 5

The charge of a particle divided by it’s mass.

Question 6

What force holds together the nucleus?

Answer 6

The strong nuclear force.

Question 7

At what distances does the strong force attract?

Answer 7

3-4fm

Question 8

At what distances does the strong force repel?

Answer 8

distances less than 0.5fm

Question 9

How do you work out the energy of a photon?

Answer 9

E = hf             E=hc/λ
E = energy
h = Planck's Constant
f = frequency
c = speed of light
λ = wavelength

Question 10

How are em waves emitted?

Answer 10

em waves are emitted when a charged particle loses it’s energy. This can happen if an electron in a shell moves to a lower shell or if a fast moving electron slows down.

Question 11

How do we calculate the wavelength of a wave in a vacuum?

Answer 11

λ = c/f

Question 12

What happens when antimatter particles and matter particles meet up with each other?

Answer 12

They annihilate each other and release photons.

Question 13

What happens in beta - decay?

Answer 13

A neutron decays into a proton, electron and an antineutrino (β- particle). A W⁻ Boson is used as an exchange particle.

Question 14

What happens in beta + decay?

Answer 14

A proton decays into a neutron, positron and a neutrino (β+ particle). A W⁺ Boson is used as an exchange particle.

Question 15

What are the six quarks in the standard model?

Answer 15

Up, down, top, bottom, charm and strange.

Question 16

What are the four gauge bosons in the standard model?

Answer 16

photon, W, gluon, Z

Question 17

What are the six leptons in the standard model?

Answer 17

Electron, electron neutrino, muon, muon neutrino, tau, and tau neutrino.

Question 18

What is a hadron?

Answer 18

Hadrons are particles and antiparticles that can interact through the strong force and all other fundamental interactions.
e.g. protons, neutrons, π mesons, K mesons

Question 19

What is a lepton?

Answer 19

Leptons are particles and antiparticles that can only interact through the weak force.

Question 20

What is the only stable hadron?

Answer 20

The proton is the only stable hadron. All others eventually decay through the weak interaction.

Question 21

What is a baryon?

Answer 21

Baryons are protons and all other hadrons that decay into protons.

Question 22

What is a meson?

Answer 22

Mesons are hadrons that do not decay into protons.

e.g. pions and kaons